Silver-cleaner.



UNITED STATES PATENT OFFICE.

JOHN B. HOEN, OF PHILADELPHIA, EENNSYLVANIA, ASSIGNOR TO THE FRANK A.ROLLING 00., INC., A CORPORATION OF PENNSYLVANIA.

SILVER-CLEANER.

Application filed February 2 1916.

To all whom it may concern:

Be it known that l, Joiix B. Hoax, a citazen of the l nited States,residing at Philadelphia, county of Philadelphia, and State ofPennsylvania, have invented certain new and useful Improvements inSilver-Cleaners; and I do hereby declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame.

It is the object of the present invention to provide means wherebytarnished metal articles such as silverware, either solid or plated,mesh bags. toilet articles and the like, and articles of gold and otherelectronegative metals, may be quickly and etlectively cleaned of thetarnish by electrolytic action instead of or preparatory to polishing.

The silver or other articles to be cleaned are immersed in an alkalinesolution in con junction with an apparatus so constructed that thesilver or the like becomes the cathode of a voltaic couple, and thecoating or tarnish is electrolytically reduced by the electric currentthus set up, and the silverware thereby rendered clean and bright.According to the present invention, the apparatus whereby this result iseffected is economical to manufacture, compact in design, rugged inconstruction, eflicient in its electrochemicall action, and convenientto use and clean.

In the drawings Figure 1 is a plan View of an apparatus suitable forcarrying out the results desired; Fig. 2 is a sectional elevationthereof on the line 2-2 of Fig. 1; and Fig. an" an enlarged fragmentaryeleration.

In the construction shown there is provided an electrode 1 of circularoutline having a fiat top, and having at its edge a. downwardlyextending flange in the form of a circumferential bead 2 (Fig. 2) whichstiltens said tlat top and raises it above the bottom of the dish pan orother container in which the apparatus is to be used, as indicated indotted lines in Fig. 2. This electrode or disk 1 consists ofelectro-positiw3 metal, as, for exampleQzinc, and its flat top has oneor more perforations 3 communieating with the shallow pocket formed between this flat top and the bottom of the dish pan or container. Securedto the zinc Specification of Letters Patent.

Patented May 9, 1916.

Serial No. 79,638.

electrode and in effective electrical connection therewith is a gridadapted to receive and support the articles to be cleaned and tomaintain good electrical connection between said articles and the zinc.The grid preferably covers substantially the entire top face of saidelectrode and has a contacting surface which is of a metal or alloyelectro-positive to the zinc, as, for example, tin, silver, solder,gold, etc. Preferably the exposed surface is of tin.

In the embodiment illustrated, the tinned grid includes a pair ofsegmental brackets and preferably of round wire, opposed to one another,and spaced from the fiattop of the disk near its periphery but withvflattened ends 6 and 7 offset at 8 and 9 (Fig. 2) and soldered to theflat top of the disk so that there may always be good electricalconnection between the disk and the brackets. Supported on thesebrackets and preferably made integral therewith by welding, are aplurality of Crossbars 10, preferably in the form of separate, straight,round rods of progressively varying length. lf iron is used for thebrackets and crossbars, the entire grid should be heavily tinned afterwelding, so that when assembled with the disk, it will throughoutpresent an exposed surface electro-negative to the zinc and well adaptedfor making contact with the silverware to be cleaned.

The electrolyte used in the dish pan or other container of Fig. 2, whensilverware or the like is to be cleaned, is an alkaline solutionprepared, for instance, by dissolving one tablespoonful of baking soda(bicarbonate of soda and one-half cup of table salt (sodium chlorid) ineach gallon of water. Preferably, but not necessarily, warm or hot wateris used. \Vhen this electrolyte is poured into the dish pan or othercontainer wherein the cleaning is to be carried out, there will beset upan electrolytic action by which the zinc or disk 1 will tend to passinto solution and reducing agents will be liberated on the tinned wiregrid, thereby reducing any oxid on the grid and rendering it bright andtherefore in good condition for making efi'ective electrical con tactwith any silverware or other articles put into the dish pan forcleaning. Owing to the quick polarization of the tinned wires and to thehigh overyolt-age of the tin, the total flow of current from the zinc tothe wires when no silverware is in the dish is ielatively small. Silverareor other articles to be cleaned are then immersed in the electrolyteand by resting on the cleaned tinned wires are placed in electricalconnection with the zinc of the disk so that current can flow from thezinc or clectro-positive' metal through the electrolyte to thesilverware with sil'nnltaneous electrolytic reduction of the oxids,sulfids and the like, which constitute the layer of tarnish on thesilverware. come out bright and of good appearance, and there is noremoval of silver from the surface of the articles but merely anelectrolytic reduction of the tarnish. The articles may then be rinsedin clear water and rubbed with a soft cloth.

During the electrolytic action the tinned grid remains clean and bright,but the zinc or clcctro positive metal of the disk becomes coated with aporous film or inerustation. llowcver. the soldered connection betweenthe wire grid and the zinc dish maintains ctfcctive electricalconnection betwcen'thc silverware and the zinc and the film or in-;rustation on the zinc or other elcctro-positive metal is porous enoughto allow the electrolytic action to go on. so that in practice, theoperation may be continued for long periods without substantial loss inefficiency. Aluminum can he used for the electropositive disk 1 and nikel-plated wires ca he used for the metal grid.

.iy making the cross-bars 10 of the grid integral with the peripheralsegments 4 and 5 as by welding thereto. a high electrical conductivityis insured. and there is no chance of loose contacts in the path ofelectric current flowing from the silverware to the zinc, and by makingthe grid large cnough to substantially cover the flat top of the disk.and with the cross-bars l0. relatively close together. as illustrated.the silverware cannot work down under the gridtribution of currentthrough the electrolyte and an equalizationof the electrolytic action onthe zinc, such as would not he bad if the cross-bars l0 rested directlyon the Zinc surface. This arrangement also tends to equalize theelectrolytic action throughout the entire surface of the silverarticles- The articles cl'san very quickly and being cleaned, instead ofconfining it to limited areas as might be the case if the electrolyticpath between the zinc and the articles to be cleaned was very short atany point.

By making the zinc electrode of circular outline it fits well in thebottom of a dish pan. or the like, and the circumferential bead holdsthe flat face of the disk spaced above the bottom of the dish pan sothat the electrolyte may contact not only with the top face. but alsowith the bottom face of the disk. The opening 3 through the disk permitsthe escape of air which might otherwise become entrapped under the disk.and it also affords a path for current through the electrolyte to theunder-surface of the disk. and while the flow of current through thisopening will ordinarily not be large.

any impairment in the eff ctiveness of the top face of the disk. asthrough abuse of the apparatus. will not render the device inoperative.for current can still llow to the lower face of the disk and cleaningwill still go on, though at a slower rate.

It has been found in practice that housc wives in order to keep theelectrolyte warm. and therefore in most effective condition, ofter placethe dish pan on a stove. and with the present arrangement thepcrforation through the disk permits limited cir cu'lation ofelectrolyte from beneath the disk or the escape of steam from beneath incase of too energetic heating. and the Zinc plate is protectcd from suchdetrimental action as might result to the zinc or to its incrustation.were there no layer of electrolyte be tween the zinc and the bottom ofthe pan. The low thermal coinlnctivity of zinc and of the imrrustationwhich forms on its active surface as an incident to use as describedherein. limits the transfer of heat through the disk and gives aparticular importance to the pocket. bounded by the circnmferen tialllangc ol the disk and lillcd always with clectrolydc which is inconnection with the main body of the electrolyte through opening 3. Bymaking the active surface of the zinc flat. and by spacing the grid wellabove that llat surface, the cleaning and drying of the active surfacemay be readily ctl'ectcd.

Changes in the apparatus shown in the drawing may be made withoutdeparting from the invention as defined by the appended claims.

I claim:

1. Apparatus for the clectroflvtic cleaning of silverware and the like.comprising a zinc electrode of circular outline having at its edge astiffening llange. and a grid consisting of segmental wire bracketsopposed to one another and spaced from the top of said electrode nearits periphery. and crossbars secured to said brackets and having asurface of tin.

:2. Apparatus for the electrolytic cleaning of silverware and the like.comprising a zinc electrode of circular outline to fit the bottom of adish pan, and a grid for said electrode consisting of segmental wirebrackets opposed to one another and spaced from the top of saidelectrode near its periphery but with oll'-set ends soldered to saidtop, and cross-bars lyin g across said brackets and secured thereto,said crossbars and brackets ha ving a surface of tin.

3. Apparatus for the electrolytic cleaning of silverware and the like,comprising a zinc electrode having a Hat top and having, at its edge adounuardly extending flange, said llat top havin; an opening permittingthe escape of air or steam from beneath said electrode and a ll'ording apath for current from the bottom l'acc thereof, and a grid for saidelectrode consisting of wire brackets oppos d to one another and spacedfrom said flat top near its periphery, but with otl set ends soldered tosaid t p. and cross-para lying across said bracl-(cts, said crossbar-sand brackets having a surface of tin.

4'. Apparatus tor the electrolytic cleaning of sibenvare and the like,com n'ising a zinc electrode of circular outline baring a flat top andhaving at its edge a downwardly ext-ending: circumlerential flange, saidfiat top having an opening permitting the escape of air or steam frombeneath said electrode and affording a path for current from the bottomface thereof, aud'n grid for said electrode comprising opposed bracketsand straight tinned bars secured thereto and spaced from the flat top ofsaid electrode to facilitate cleaning thereof and adapted to receive andsupport the articles to be cleaned. said grid maintaining goodelectrical connection between said articles and the zinc.

73 Apparatus for the electrolytic clcanin; of silverware and the like.comprising a Zinc electrode of circular outline having a. flat top andhaving at its edge a downwardly extending circunifcrential flange, saidflat top bai ing an opening permitting the escape of air or steam frombeneath said electrode and all'ording a path for current from the bottomt'ace thereof. and a grid For said electrode consisting of opposed \virebraclc ets and tinned \vires welded thereto and spaced from the top ofthe electrode to equalize the fltl'd' of current. therefrom. and tofacilitate cleaning of the electrode. said wires being adapted toreceive and support the articles to be cleaned and to maintain goodelectrical connection between said articles and the zinc.

0. Apparatus for the electrolytic cleaning of silverware and the like,comprising a zinc electrode of circular outline having a flat top andhaving at its edge a downwardly extending circumferential flange, saidflat top ha ring an opening permitting the escape of air or steam frombeneath said electrode and all'ording a path lor current, from thebottom face thereof, and a grid for said electrode consisting ofsegmental Wire brackets Uppflnttl to one another and spaced from saidflat top near its periphery, but with otl-s t ends soldered to said topand cross-burs lying across said brackets and welded thereto, saidcross-bars and brackets having a surface of tin.

7. Apparatus for the electrolytic cleaning of silverware and the like,comprising a zinc electrode of circular outline having a flat top andhaving at its edge a downwardly extending circuml'erential bend tostill'en said flat top and to raise it above the bottom of the containerin which the electrolyte is held, said flat top ha ing an openingpermuting the escape of air or steam from beneath said electrode andatlording a path for current from the bottom face thereof, and a gridfor said electrode consisting of segmental wire brackets opposed to oneanother and spaced from said that top near its periphery, but withoff-set ends soldered to said top and cross-bars secured to saidbrackets, said cross-bars and brackets having a surface of tin.

8. A paratus for the electrolytic cleaning of silverware and the like,comprising" a zinc electrode of circular outline having a flat top andhaving at its edge a downwardly extending circmnl erential bead tostiffen said flat top and to raise it above the bottom of the containerin which the electrolyte is held. said flat top having" an openingpermitting: the escape of air or steam from beneath raid electrode andall'ordingj path for current. f om the bottom face thereof, and a gridfor said electrode consisting of c;jnici'3t::l wire brackets opposed toone another and spaced from said flat top near its periphery but withoil-set and flattened ends oldered to said top, and er0ss-bars in theform of separate straight, round rods of progressively varying lengthlying across said brackets and welded thereto, said crossbars andbrackets liming a surface of tin; substantially as described.

in testimony whereof I allin my signature.

JOHN B. HOEN.

\v ituesses:

ll. ll. \VILLIAMsoN, J12, ute, Orr.

